Chain saw

Patent metadata

Field	Value
Publication number	US-11833656-B2
Application number	US-202117551478-A
Country	US
Kind code	B2
Filing date	Dec 15, 2021
Priority date	Dec 24, 2020
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

A chain saw may include a saw chain, a guide bar to which the saw chain is attached, a sprocket configured to run the saw chain along a periphery of the guide bar, a prime mover configured to rotate the sprocket, an oil tank configured to store oil to be supplied to the saw chain, a housing that houses the prime mover and the oil tank, a bolt protruding from the housing and penetrating a hole disposed in the guide bar, a nut screwed onto the bolt to fix the guide bar to the housing, and a heat dissipating structure configured to dissipate heat from the bolt to the oil in the oil tank.

First claim

What is claimed is:

1. A chain saw comprising:
a saw chain;
a guide bar to which the saw chain is attached;
a sprocket configured to run the saw chain along a periphery of the guide bar;
a prime mover configured to rotate the sprocket;
an oil tank configured to store oil to be supplied to the saw chain;
a housing that houses the prime mover and the oil tank;
a bolt protruding from the housing and penetrating a hole disposed in the guide bar;
a nut screwed onto the bolt to fix the guide bar to the housing; and
a heat dissipating structure configured to dissipate heat from the bolt to the oil in the oil tank.

2. The chain saw according to claim 1 , wherein the heat dissipating structure comprises a heat dissipating member attached to and extending from a lower portion of the bolt, wherein at least a part of the heat dissipating member is disposed in the oil tank.

3. The chain saw according to claim 2 , wherein the heat dissipating member comprises a heat dissipating fin constituted of a metallic material.

4. The chain saw according to claim 2 , wherein a liquid surface of the oil is located above a lower end of the at least a part of the heat dissipating member in a state in which the chain saw is placed on a ground surface when the oil having an oil amount corresponding to a first ratio of a capacity of the oil tank is stored in the oil tank.

5. The chain saw according to claim 4 , wherein the first ratio is 50% of the capacity of the oil tank.

6. The chain saw according to claim 2 , wherein part of the heat dissipating member disposed in the oil tank extends from an inner surface of the oil tank to at least 10% of a length of the oil tank with respect to a direction in which the bolt extends.

7. The chain saw according to claim 1 , wherein the bolt penetrates the oil tank from an outside of the oil tank to an inside of the oil tank, a portion of the bolt inside the oil tank constitutes the heat dissipating structure, and the portion of the bolt inside the oil tank includes a portion disposed in the oil tank and extending from an inner surface of the oil tank by at least 10% of a length of the oil tank with respect to a direction in which the bolt extends.

8. The chain saw according to claim 7 , wherein a liquid surface of the oil is located above a lower end of the portion of the bolt inside the oil tank in a state in which the chain saw is placed on a ground surface when the oil having an oil amount corresponding to a first ratio of a capacity of the oil tank is stored in the oil tank.

9. The chain saw according to claim 8 , wherein the first ratio is equal to or less than 50% of the capacity of the oil tank.

10. The chain saw according to claim 1 , wherein the guide bar comprises a cutting part disposed between the housing and a front end of the guide bar in a longitudinal direction of the guide bar, and
a length of the cutting part in the longitudinal direction is equal to or less than 250 mm.

11. The chain saw according to claim 1 , wherein the prime mover is a motor.

12. The chain saw according to claim 11 , further comprising a battery pack configured to be detachably attached to the housing, wherein
the motor is configured to operate using electric power supplied from the battery pack.

Assignees

• Makita Corp

Inventors

• Oishi Kohei
• Sunazuka Ryo
• Watanabe Yoshifumi

Classifications

• B25F5/008 Primary

  Cooling means · CPC title

• B27B17/02

  Chain saws equipped with guide bar (B27B17/06 takes precedence) · CPC title

• B27B17/08

  Drives or gearings; Devices for swivelling or tilting the chain saw · CPC title

• B27B17/12

  Lubricating devices specially designed for chain saws · CPC title

• B27B17/00 Primary

  Chain saws; Equipment therefor {(slotting or mortising machines equipped with chain cutters B27F5/06)} · CPC title